The invention relates to a lighting device for passenger conveyors such as escalators and travelators.
From DE-A 38 43 090 a moving staircase or moving pavement comprising at least one balustrade and a lighting device extending at least in part along the balustrade as well as a supporting device for a handrail running on the balustrade is known. The supporting device consists of at least one translucent profile, more particularly of a plastics material, comprising a cavity for accommodating the lighting device. The supporting device includes a conduit for wiring or the like located concealed in the region of the moving staircase or pavement comprising the lighting device. The lighting device extends in the form of a plurality of fluorescent tubes between the upper and lower head of the balustrade. The drawback is this arrangement is that due to the use of conventional fluorescent tubes as the lighting device, the power supply automatically needs to be safeguarded in addition to the flourescent tube. Electricity in the region of passenger conveyors is always a potential hazard, especially as regards vandalism or the like. Further, having fluorescent tubes as the lighting device is a disadvantage since these can easily become defective due to wear and tear or damage due to the cover receiving impact, necessitating a not inconsiderable time to replace such defective components.
To obviate this problem DE-C 42 09 505 proposes an escalator having a transparent balustrade, a flexible handrail guided by the top edge of the balustrade and a lighting device arranged in a cavity underneath the handrail. This lighting device is formed of fibre light-guides consisting of a material that guides beams of light entering the light-guide at at least one location substantially parallel to the handrail. The light emission surface area is formed by the surface area of the light-guide facing downwards with the cross-section of the light-guide being configured rectangular and tapered over the length of the light-guide and the cross-sectional surface area of the cavity remaining in each case being filled out with a counterlayer. Although light can be introduced into the cross-section of the light-guide already via an active light source and is emitted oriented, the drawback in this arrangement is due to the fact that the fibres need to be oriented as well as due to the taperered contour of the light guide a not inconsiderable expense to the fabrication of the light-guide. Thus, these light-guide are considerably more expensive. In addition to this, due to the selected cross-sectional shape, the profile accommodating the light-guide is also complicated unduly.
EP-A 676 362 discloses a lighting device incorporating light-guides for moving staircases or pavements in which light is guided from at least one central light source to lighting points of the moving staircase or pavement by light-guides extending at least in part along the balustrade. The lighting points are passive light sources. Each light source includes a mounting device, a light-guide receptacle and preferably integrated optics, distributed over the system spatially discrete and connected via separate discrete light-guides configured as a glass fibre to the light-guide connection of a central active light source with a lighting fixture in a housing. Even though, lighting of the step or pallet track can be achieved by incorporating a plurality of so-called spots as passive light sources in the skirting, undue expense is involved since a separate optical fibre cable needs to be put down to each spot and likewise a plurality of ports needs to be incorporated in the skirting to receive the spots which also require securing there.